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\begin{equation*}\int\frac{x^2\;dx}{(ax + b)^n} = \frac{1}{a^3}\left(-\frac{1}{(n- 3)(ax + b)^{n-3}} + \frac{2b}{(n-2)(a + b)^{n-2}} - \frac{b^2}{(n - 1)(ax + b)^{n-1}}\right) \qquad\mbox{(for } n\not\in \{1, 2, 3\}\mbox{)}\end{equation*}
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